Ignition burner



Oct. 29, 1929. T.G.OGHLAN 1,133,6 7

IGNITION BURNER Filed May 1927 2 Sheets-Sheet 1 d: z M-JNVENTOR ATTORNEYS Oct. 29, 1929. T. G. COGHLAN IGNI TION BURNER Filed May 1927 2 Sheets-Sheet 2 m Lm m w? INVENTOR Patented Oct. 29, 1929 PATENT OFFICE THOMAS G. COGHLAN, 0F ELIZABETH, NEW JERSEY IGNITION BURNER Application filed May 9, 1927. Serial No. 189,843.

My present invention relates to furnaces, particularly such as are designed primarily to burn solid fuel and are equipped with mechanism to carry the solid fuel into the furnace for combustion. My invention will be best understood from the following description and the annexed drawings in which Fi 1 is a vertical section through a furnace emlmdying an illustrative form of my invention; Fig. 2 is a fragmentary horizontal section on the line 22 of Fig. 1; Fig 3 is a View of the door frame closed by the door carrying the ignition burner and showing the peep-hole door swung open; Fig. 4 is a fragmentary section in elevation through the furnace wall on the line 4-4 of Fig. 3; and Fig. 5 is a fragmentary section in plan through the furnace wall on the line 5=5 of Fig. 3.

Like reference characters indicate like parts in the several views.

In the illustrative embodiment of my invention, the steam boiler, which I have chosen for purposes of illustration, is provided with water tubes 10, uptake headers 11 and downtake headers 12, all connected together and to the boiler in the usual manner. The usual bafiles, such as 13, direct the gases back and forth in a plurality of passes over the boiler tubes 10. A chain grate stoker 15, in the lower part of the combustion chamber, carries fuel rearwardly from a hopper 16 located in front of the furnace to dump the resulting ash into the ash hopper through the opening 17 adjacent the rear wall 18. Preferably the grate is operated with forced blast, with the blast delivered through separate compartments, the air pressures in which may be separately controlled.

At the frontof the stoker 15 is a pair of curved arches 19 and 20 forming a combustion arch over the front of the grate. Arches 21 and 22, extending upwardly and forwardly over the rear of the stoker, form, with the arches 19 and 20, a lower or primary combustion chamber 24 ending at its upper extremity in a throat or passageway 23. Side walls 25 of the furnace enclose thefurnace chamber, as shown, and support the fuel igniting means to be hereinafter described, it being understood that preferably each side wall will be provided with such an igniting means.

A flat roof 26 and walls 27 and 28 define an upper or secondary combustion chamber 29 immediately below the tubes 10 of the boiler. Air inlets 30 communicate with the throat 23 between the two combustion chambers to aid the combustion of unburned gases passing that point. The entire structure is carried on steel framework in any suitable manner.

The side wall 25 of the furnace is provided with an inspection doorway and burner entry port 31 communicating under the arch 20 with the lower furnace chamber 24:. The front wall 32 of the port 31 extends forwardly to flare the port inwardly so that a forwardly extending fiamefrom the nozzle or burner 33 will be approximately equidistant from opposite sides of the port. The upper and lower port faces 35 and 36 slope upwardly and downwardly, respectively, thus increasing the inward flare or size of the ort on the end adjacent the furnace chain er. The wall 25 supports on its exterior face a metallic door frame 38 constructed to frame the opening 31 through the wall. The frame 38 is secured to the side wall 25 partly by angles 39 extending from the inner face of the frame.

The frame 38 has pairs of perforated lugs 40 and 41 extending from opposite vertical sides. The pair of lugs 40 hingedly mounts a door 42 arranged to carry the burner 33. The other pair of lugs 41 hinges a peep-hole door 43 to swing oppositely to the door 42. Either door may thus close the port while the other door is swung back against the side wall 25 of the furnace and is out of the way of the door that is in use.

The burner carrying door 42, shown as covering the port hole, is pierced at two points for the passage of pipes Q4: and 45, one to convey fuel I oil and the other to convey steam. The pipes 44 and 45 are joined at their inner extremities by the atomizing burner nozzle 33. The two pipes are slidably mounted in the door to project the burner 33 to varying distances within the furnace.

, The exteriorly located connections to the pipes are provided with the usual control valves to regulate the amounts and proportion of steam and fuel used. Flexible hose connections joining the pipes to suitable fuel supply and steam pressure, respectively, permit the adjustable movements of the burner nozzle within the furnace, to move the jet of flame or to allow movement of the burner, to a position that will permit opening and closing movements of the door. A clamp 47 engaging both pipes serves as a stop to limit inward movement of the burner. A latch 48 secures the door in closed position against the face of the door frame.

The second or peep-hole door 43 covers the port when the burner is not in use, as when the furnace is well started and burning smoothly. The door 43 is hinged to the lugs 41 on the side against which the burner door 42 is latched. as has been noted above. It is swung completely out of the way when the burner door is in use. A peep-hole 50 through the door is covered by a small cap 51 removable to permit inspection of the furnace interior when the door 43 covers the port 31. A latch 52 secures the door in closed position against the frame. Each door comprises a metallic shell which mav be lined with asbestos and filled in with fire brick.

It will be noted that burner 33, in the illustrative embodiment, is directed at an angle toward arch 19 and is beneath arch 20. Consequently, when the burner is ignited, these arches become heated rapidly. The heat of the arches is reflected to the fuel on the front of the stoker and therefore brings this fresh fuel rapidly to the ignition point. This arrangement is particularly useful in starting up a boiler when it is cold. The ignition burners described provide a means by which the arches over the fuel inlet can be heated and the fresh fuel brought to the ignition point.

In the normal operation of the furnace. the ignition arch serves to ignite the coal as it is fed into the furnace. During the layover period. the arch cools to such an extent, that before being able to resume operation, the arch mustagain be brought to a temperature high enough to ignite the fuel. Direct heating as described herein effects a saving of time overheating of the arch by the gradual work ing forward of the fire on the grate, according to usual practice or by directing the flame against the bed of fuel beneath the arch. Moreover, the latter scheme might prove injurious to the grate, whereas the arch is well able to stand the heat.

It will be obvious that various modifications may be made in this device within the limits of this invention;

I claim:

1. A furnace having a fuel feeding grate, said furnace having an arch over the fuel inlet end of said grate, and means to direct a stream of burning finely divided fuel between the arch and the grate and against the arch 2. A furnace having a fuel feeding grate, said furnace having an arch over the fuel inlet end of said grate, and means to direct a stream of burning finely divided fuel between the arch and the grate and against the arch, said means comprising a burner extending through the side wall of the furnace and directed at an angle to the face of the arch extending across the fuel inlet.

In a furnace, a grate, an ignition arch disposed in position to ignite fuel thereon, and a burner adapted to direct a stream of burning fuel adjacent said arch.

4. In a furnace, a grate, an ignition arch disposed in position to ignite fuel thereon, and means independent of the grate to heat said arch and thereby to ignite the fuel on said grate.

5. In a furnace, a grate, an ignition arch disposed in position to ignite fuel thereon, and a burner mounted in a wall of the furnace above the grate and adapted to direct a stream of burning fuel adjacent said arch.

6. In a furnace, a grate, two ig iition arches over one end thereof and one disposed above the other, and means independent of the grate to heat said arches and thereby ignite the fuel on the grate.

7. In a furnace, a grate, two ignition archesv over one end thereofand one disposed above the other, and a burner adapted to direct a Strfiilfll of burning fuel beneath the upper arc 8. In a furnace, a grate, two ignition arches over one end thereof and one disposed above the other, and a burner adapted to direct a streamof burning fuel beneath the upper arch and adjacent the lower one.

9. In a furnace, a grate, an ignition arch having a portion thereof extending over the grate, and a burner mounted above the grate and adapted to project a stream of burning fuel beneath said portion of the arch.

10. In a furnace, a grate, an ignition arch comprising one portion extending upwardly from the grate and another portion extending over the grate. and a burner adapted to direct a stream of burning fuel beneath said last-named portion.

11. In a furnace, a grate, an ignition arch comprising one portion extending upwardly from the grate and another portion extending over the grate, and a burner adapted to direct a stream of burning fuel beneath said lastnamed portion and adjacent said first-named portion.

12. In a furnace, a grate, an ignition arch disposed above said grate, a door closing an opening in a wall of the furnace above the grate, and a burner mounted on said door and adapted to direct a stream'of burning fuel adjacent said arch when the door is closed.

13. In a. furnace, a grate, an ignition arch dis in 'tion to ignite fuel thereon, a wa of the ace having an opening there'- in a .door adapted to close said opening and a urner on said door and adapted to direct a stream of burning fuel against said arch when the door is closed. 7

THOMAS G. COGHLAN. 

